Il problema dell’identificazione di forme: considerazioni sull’analisi fisionomica

In the radiological diagnostic imaging, a right determination of shapes is a primary component to diagnose a disease or to assert its absence; the quality of the analysed images depends on technological factors, such as resolution, contrast or total energy, and also on postural factors: the correct positioning of the patient is crucial in order to correctly appreciate both the particular and the total anatomical segment in order to make a good diagnosis. In addition, except in particular situations, for instance such a search of a right oblique representation of a fracture or occult infringement, that are cases in which a specific results are sought, and that requires different actions from time to time, the setting and use of standard common criteria for the acquisition are of utmost importance. The criteria must be able to guarantee the high quality, but mainly the reproducibility of the result of the diagnostic examination, and they are the basis of all medical radiology schools, in order to make the result of the acquisition the less dependent as possible from the involved operator. The identification of particular forms is a task normally delegated to the professional ability of an experienced person of the domain who, as such, is subject to evaluation errors not so much for imperfection or superficiality, but for the intrinsic limitations of 'eye system' and for the bi-dimensionality of the image, that is the result of a projection of a three-dimensional body on a plan. In analogy to the difficulties associated with the aforementioned diagnostic imaging, in approaching the problems associated with the correct identification of shapes, it may be useful to start from faces identification problems; It is an activity that belongs to us and we constantly do, and therefore it will be easier to comprehend the intrinsic difficulties associated with the perception of physionomic forms. The techniques used for the identification of subjects and the operational difficulties that arise when an identity must be attributed using the physionomic aspects extracted from photographic documents will be analyzed; This activity is very similar to the morphological perception of anatomical structures and presents the same difficulties.